Medical implant system

ABSTRACT

An implant including a bone fixture configured to anchor to bone of a recipient, and a structural component configured to be connected to the bone fixture and connect a functional component of the implant to the bone fixture, wherein at least one of the bone fixture or the structural component includes a deformable element configured to deform to form an anti-microbial seal between the bone fixture and the structural component, and the at least one deformable element and the respective at least one bone fixture or structural component form a monolithic structure.

CROSS-REFERENCE TO RELATED APPLICATIONS

The present application is a continuation application of InternationalPatent Application No. PCT/AU2010/000401, filed on Apr. 9, 2010,designating Goran Bjorn of Sweden and Dr. Marcus Andersson, also ofSweden, as inventors, which claims priority to Australian ProvisionalPatent Application No. 2009903789 entitled “Implant Device” filed on 13Aug. 2009, and Australian Provisional Patent Application No. 2009905020entitled “Implant Device” filed on 14 Oct. 2009, the entire content ofeach of these applications being hereby incorporated by reference hereinin their entirety.

BACKGROUND

1. Field of the Invention

The present invention relates generally to bone conduction devices, andmore particularly, to infection prevention measures associated withpercutaneous bone conduction devices.

2. Related Art

Bone-anchored medical implant systems are used to connect or fixatehearing devices to a recipient, directly to the bone or skull of therecipient. Some applications include hearing implants such as boneconduction devices marketed by Cochlear Bone Anchored Solutions AB inSweden. Such bone conduction devices sometimes comprise, in the case ofpercutaneous bone conductions devices as is shown by way of example inFIG. 27 d in black-box format, an external, removable unit 2759including a vibrator 2761 which transforms sound into mechanicalvibrations. Percutaneous bone conductions devices conduct thosemechanical vibrations via an abutment 2763 and a bone fixture 2765 ofthe implant, into the bone of the skull. Passive transcutaneous boneconduction devices conduct those mechanical vibrations through skin ofthe recipient to an implantable component which includes a bone fixture.The vibrations are transmitted mechanically via the skull bone andthereafter to the inner ear of a person with impaired hearing and allowsfor the hearing organ to register the sound. A hearing device of thebone conduction device type typically includes an anchoring element orfixture, in the form of, for example, an implanted titanium screw,corresponding to the bone fixture, installed in the bone behind theexternal ear and the sound is transmitted via the skull bone to thecochlea (inner ear), irrespective of any disease, injury or otherdysfunction of the middle ear. In percutaneous bone conduction oranchoring arrangements, the skin is penetrated, which makes thevibratory transmission very efficient. This arrangement can also be usedin connection with facial prostheses, such as, for example, some ofthose marketed by Cochlear Limited, Australia.

The implants which are used with percutaneous bone conduction devicesare sometimes provided in two pieces. One piece comprises thescrew-shaped anchoring element (fixture or anchor) and the other piececomprises the abutment, which penetrates the skin. This two-piecedesign, in many exemplary embodiments, allows the surgical implantationto be carried out as a two-step procedure. In the first step ofimplanting such a two-pieced design, the fixture is inserted andmaintained unloaded during a healing period of some months or so. Afterthis healing period the second step of the surgical procedure, i.e. theconnection of the abutment by means of an abutment screw, is executed.The two-part design may allow for the implants to be up-graded, ifdesirable, without removing the fixture or anchor. Furthermore, if theabutment is damaged, it can then be replaced without need of removal ofthe bone anchored screw or fixture.

A situation sometimes experienced with bone conduction devices ingeneral, and percutaneous implant devices in particular, is the risk ofinfections and inflammation. This exists sometimes at the tissue-implantinterface. The infections are a result of bacterial colonization at thearea around the interface between the bone fixture and the abutment.This problem can be persistent and cause infections. Cleaning of theinterface has utility, but even regular cleaning and disinfection is notalways entirely successful. The risk of infections may also exist at theinterface between separate components of totally implantable prostheses.

With respect to a percutaneous bone conduction device, the bacteria mayenter the implant-tissue interface by two different routes—an externalroute on the external surface of the abutment, and an internal routewhich starts at the top of the abutment and travels via internal parts(screw connection) of the implant system and may exit at theabutment-fixture-soft tissue junction or interface. The external routeis the most open route, but the bacteria may also reach theimplant-tissue interface from the internal route, known as the internalmicro-leakage pathway.

SUMMARY

Some aspects of the present invention are generally directed to animplant including a bone fixture configured to anchor to bone of arecipient, and a structural component configured to be connected to thebone fixture and connect a functional component of the implant to thebone fixture, wherein at least one of the bone fixture or the structuralcomponent includes a deformable element configured to deform to form ananti-microbial seal between the bone fixture and the structuralcomponent, and the at least one deformable element and the respective atleast one bone fixture or structural component form a monolithicstructure.

Some other aspects of the present invention are generally directed to animplant, comprising a bone fixture configured to anchor to bone of arecipient, a structural component configured to be connected to the bonefixture and connect a functional component of the implant to the bonefixture, and a screw configured to bolt the structural component to thebone fixture, wherein the implant includes an anti-microbial sealbetween the structural component and the screw.

Some other aspects of the present invention are generally directed to animplant, comprising, a bone fixture configured to anchor to bone of arecipient, and a structural component configured to be connected to thebone fixture and connect a functional component of the implant to thebone fixture, wherein at least one of the bone fixture or the structuralcomponent includes a deformable element configured to plastically deformto form an anti-microbial seal between the bone fixture and thestructural component.

Some other aspects of the present invention are generally directed to amethod of attaching an abutment to an implanted bone fixture to form apercutaneous implant, comprising positioning the abutment in contactwith the implanted bone fixture, and applying a torque of about 15 Ncmor more to a component of the percutaneous implant threadably engagedwith the implanted bone fixture, thereby driving the abutment towardsthe bone fixture via reaction against the implanted bone fixture,wherein the applied torque is sufficient to at least one of deformmaterial of at least one of the bone fixture and the abutment to form ananti-microbial seal between the bone fixture and the abutment, or deformmaterial of at least one of an abutment screw and the abutment to forman anti-microbial seal between the abutment screw and the abutment.

BRIEF DESCRIPTION OF THE DRAWINGS

Embodiments of the present invention are described below with referenceto the attached drawings, in which:

FIG. 1—shows an example of a medical implant system to which variousaspects of the present disclosure may be applied;

FIG. 2—shows a cross section of the medical implant system of FIG. 1;

FIG. 3—shows a perspective view of the medical implant system of FIG. 1;

FIG. 4—shows a cross section exploded view of the components of themedical implant system of FIG. 1;

FIG. 5 a—shows one embodiment of an abutment screw of one aspect of thedisclosure;

FIG. 5 b—shows a cross section of the abutment screw of FIG. 5A;

FIG. 5 c—shows a close up view of the deformable element of FIG. 5B;

FIG. 6—shows a cross section of the abutment screw of FIG. 5A in anabutment;

FIG. 7—shows a close-up cross section view of a seal provided betweenthe abutment screw of FIG. 5A and the abutment;

FIG. 8—shows a cross section of an alternative embodiment of theabutment screw of FIG. 5A;

FIG. 9 a—shows a cross section of yet a further alternative of theabutment screw of FIG. 5A;

FIG. 9 b—shows a perspective view of the abutment screw of FIG. 9A;

FIG. 10—shows a close-up cross section view of a seal provided betweenthe abutment screw of FIG. 9 a and the abutment;

FIG. 11—shows a perspective view of one embodiment of an abutment;

FIG. 12—shows a cross section of the abutment of FIG. 11;

FIG. 13—shows a close-up view of a seal provided between the abutmentscrew and the abutment of FIG. 11;

FIG. 14—shows a cross section of one embodiment of a fixture;

FIG. 15—shows a perspective view of one embodiment of an abutment foruse with the fixture of FIG. 14;

FIG. 16—shows a perspective view of another embodiment of an abutmentfor use with the fixture of FIG. 14;

FIG. 17—shows a perspective view of yet another embodiment of anabutment for use with the fixture of FIG. 14;

FIG. 18—shows the abutment of any one of FIGS. 15 to 17 in place in thefixture of FIG. 14;

FIG. 19—shows a close-up view of the seal provided by the arrangement ofFIG. 18;

FIG. 20—shows a different embodiment of an abutment;

FIG. 21—shows the abutment of FIG. 20 engaging with a fixture;

FIG. 22—shows a close-up of a seal provided by the arrangement of FIG.21;

FIG. 23—shows an embodiment of a medical implant system with a sealprovided between the abutment and the abutment screw;

FIG. 24—shows another embodiment of a medical implant system with a sealprovided between the abutment and the fixture;

FIG. 25—shows another embodiment of a medical implant system with a sealprovided between the abutment and the abutment screw as well as betweenthe abutment and the fixture;

FIG. 26 a—shows a flow chart of a method of implanting a medical implantsystem;

FIG. 26 b—shows a specific example of the method of FIG. 26 a;

FIG. 27 a—shows a cross section of the arrangement of the first step ofthe method of FIG. 26 b;

FIG. 27 b—shows a cross section of the arrangement of the second step ofthe method of FIG. 26 b; and

FIG. 27 c—shows a cross section of the arrangement of the third step ofthe method of FIG. 26B;

FIG. 27 d—shows in black-box format a functional conceptual externalremovable unit of a percutaneous bone conduction device including avibrator, along with an implant;

FIG. 28—shows a close-up cross section view of a seal provided betweenthe abutment screw of FIG. 5 a and the abutment in an alternateembodiment;

FIG. 29—shows a close-up cross section view of a seal provided betweenthe abutment screw of FIG. 9 a and the abutment in an alternateembodiment;

FIG. 30 a—shows a close-up view of a seal provided between the abutmentscrew and the abutment of FIG. 11 in an alternate embodiment;

FIG. 30 b—shows a close-up view of the seal provided by the arrangementof FIG. 18 in an alternate embodiment;

FIG. 31—shows an alternate embodiment of a medical implant system with aseal provided between the abutment and the abutment screw;

FIG. 32—shows another embodiment of a medical implant system with a sealprovided between the abutment and the fixture; and

FIG. 33—shows another embodiment of a medical implant system with a sealprovided between the abutment and the abutment screw as well as betweenthe abutment and the fixture.

DETAILED DESCRIPTION

FIG. 1 shows a side view of a medical implant system 100. The implantsystem has an abutment 10 that enables a hearing device to be coupledthrough a percutaneous connection to a bone anchoring device in the formof fixture 20. Abutment 10 is connected to fixture 20. Fixture 20 has abase collar 21 and screw threads 22. In use, screw threads 22 is screwedinto bone of the recipient (sometimes herein also referred to as theuser) to fixate and retain fixture 20 to the user's skull.

As can be seen in FIG. 2, which shows a cross section view along theline A-A′ of FIG. 1, abutment 10 is connected to and retained to fixture20 by abutment screw 30. Abutment screw 30 has head 31, a well 32 withinthe head 31 to receive an insertion tool or the like, and an apicalouter screw threaded section 34 on an elongate main body 33. In someexamples, abutment screw 30 may be an M 1.8 titanium screw and the well32 in head 31 may be a tubular hex configuration for receiving andcooperating with the insertion tool (not shown). The apical outer screwthreaded section 34 engages with inner screw thread 23 of the fixture 20upon turning of the insertion tool.

FIG. 3 shows a perspective view of the medical implant system 100. Inthis view, the abutment interior 13 is visible, showing the abutmentinterior base 14. Also visible in this view is abutment screw 30 withhead 31 and hexagonal well 32. The fixture 20 with base collar 21 andouter screw thread 22 is also visible.

FIG. 4 shows a cross section view of three constituent parts of themedical implant system 100, with those parts separated from one anotherfor clarity. There shown are abutment screw 30, abutment 10 and fixture20.

FIG. 5A shows an exemplary embodiment of abutment screw 30. Inparticular, abutment screw head includes a base 35 which includes adeformable element in the form of a flange 36, which is angled downwardsand outwards away from the head at a flange angle of about 10 degrees(in one example), as is more clearly seen in FIG. 5C. FIGS. 5B and 5Cshow a cross section view of the abutment screw 30 of FIG. 5A. In theseviews, the deformable element in the form of the flange 36 is moreclearly visible.

In one embodiment, the outer portion of the flange 36, corresponding toat least part of the deformable element of the abutment screw 30, has aflat portion 37 (see FIG. 5C) which, in use, rests on a correspondingcontact surface, in this case, the abutment interior base 14 as shown inFIG. 6. The deformable element is able to deform to form a seal. In oneexample, when the abutment screw 30 is screwed down into the inner screwthread 23 of fixture 20, flat portion 37 comes into contact with thecorresponding contact surface or abutment interior base 14. When theabutment screw 30 is screwed further downwards, the deformable elementcorresponding to flange 36 with flat portion 37 is pressed downwards(which may cause the edge to move outwards) against the correspondingcontact surface or abutment interior base 14 and thereby deform toprovide a seal between the abutment screw 30 and the correspondingcontact surface, in this case abutment interior base 14. In other words,the deformable element deforms a sufficient amount to provide a sealbetween the abutment screw 30 and the abutment 10, upon tightening ofthe abutment screw 30.

In other examples, the deformable element may deform upon application ofdownward pressure on the implant system or on a part thereof, such as onthe screw head 31.

In the various examples detailed herein and/or variations thereof, thetype of deformation may be plastic, elastic or a combination of both.

FIG. 7 shows a close up view of this engagement between the abutmentscrew 30 and the abutment 10, and in particular, shows how thedeformation of the deformable element as flange 36 and the flat portion37 is deformed and pressed into the surface of the abutment interiorbase 14, to provide a seal. In some cases, the corresponding contactsurface, in this case the abutment interior base 14, may itself alsodeform slightly to further increase the seal formed therebetween. In thesame vein, FIG. 28 shows a close up view of engagement between theabutment screw 30 and the abutment 10 in an alternate embodiment, whichdepicts the flange 36 being pressed into the surface of the abutmentinterior base 14, to provide a seal. As will be understood from FIG. 28,in this alternate embodiment, the corresponding contact surface, in thiscase the abutment interior base 14, may itself deform slightly tofurther increase the seal formed therebetween. The degree of resultingdeformation of the abutment screw and/or the abutment may vary betweenembodiments. In some embodiments, all or substantially all of theoverall deformation may occur in the abutment screw 30, while in someembodiments, all or substantially all of the deformation may occur inthe abutment 10, while in some embodiments, the amount of deformationmay be more evenly distributed between these two components.

As the contact surface increases by the deformation of the flange 36and/or the abutment interior base 14, surface imperfections between thecontacting surfaces might be compensated for, which reduces any gaps orholes for microbes (including fungi and bacteria) to pass through fromthe outside into the inside of the abutment.

This thereby provides a seal at the abutment and abutment screwinterface, to reduce the risk of bacterial infection via the microleakage pathway.

While the screw head 31 of abutment screw 30 may in some embodiments,have a well 32 as shown in FIGS. 5A, 5B, 5C and 6, which may assist inproviding the deformable element as flange 36, in other embodiments,head 31 need not have a well. Further, the deformable element may beprovided by any suitable structure, and may include the provision of anannular relief 38 above flange 36 to enhance the deformation, as shownin FIG. 8.

The screw head 31 of abutment screw 30 may in some embodiments, have ascrew thread which may assist in providing the deformable element asflange 36 (not shown).

In another embodiment, as shown in a cross section view in FIG. 9A, thedeformable element may be provided on the base of the head 31 by way ofan annular ring 39 extending about the outer edge of the abutment screwhead base 35. FIG. 9B shows a perspective view of this arrangement. Asin the previous example, when abutment screw 30 is tightened intoposition, the deformable element in the form of annular ring 39, isdeformed so as to form a seal between the abutment screw 30 and theabutment 10. FIG. 10 shows a close up view of this seal formed by thedeformation of the deformable element. Again, in some cases, theabutment interior base 14 may also be slightly deformed. In the samevein, FIG. 29 shows an alternate embodiment where the deformable elementis located again on the interior 14 abutment 10, and element 39 pressesinto the abutment 10, thereby forming a seal. in another embodiment, thedeformable element in the form of the annular ring may be provided onthe abutment itself. As may be seen from FIG. 10 the deformable elementmay be a protrusion having a triangular cross-section or semi-circularcross section extending from a generally planar surface of a componentof the medical implant.

FIG. 11 shows a perspective view of abutment 10 showing abutmentinterior 13 providing an abutment receiving well for receiving theabutment 10, and abutment interior base 14. Without abutment screw 30,the through bore 16, into which abutment screw 30 is inserted in use, isvisible. In this embodiment, the deformable element is provided by anannular ring 17 surrounding the through bore 16. FIG. 12 shows a crosssection view of abutment 10 with annular ring 17 surrounding throughbore 16. Again, as abutment screw 30 is inserted into through bore 16and tightened, the base 35 (in this case providing the correspondingcontact surface) of head 31 will be compressed over deformable element,in this case, annular ring 17, so as to deform it to provide a sealbetween abutment screw 30 and abutment 10. This again provides a barrierto bacteria entry into the micro leakage path and reduces risk ofinfection. In this case, the base 35 of head 31 may be planar ratherthan angled as in a previous example.

FIG. 13 shows a close up view of the seal so formed, showing thedeformation of deformable element, in this case, annular ring 17. FIG.30 a shows an alternate embodiment where the deformable element islocated on the abutment screw 30 and element 17 presses into the screw30, thereby forming a seal.

In one example, the height of annular ring 17 is about 0 05 mm and thewidth of annular ring 17 is about 0.05 mm (prior to deformation). Ofcourse, any other suitable dimensions may be used, including but notlimited to about 0.01 mm to about 0.1 mm, about 0.04 mm, about 0.06 mm,about 0.03 mm and about 0.07 mm or any combination thereof.

The above embodiments have provided examples of forming the seal betweenthe abutment screw 30 and the abutment 10. In other embodiments andaspects, the seal may alternatively, or also, be formed between thefixture 20 and the abutment 10, as will now be detailed.

In one embodiment of this aspect, as shown by way of example in FIG. 14,fixture 20 is provided with an annular corner 26 on lip 25 of theabutment receiving well, which defines the fixture interior 24. Theabutment base 12 of abutment 10 is received in fixture interior 24 to beretained by tightening the abutment screw 30 as previously described.FIGS. 15, 16 and 17 show various examples of abutment 10 configurationsthat may be used in this aspect.

In some exemplary embodiments of this aspect of the present invention,the fixture interior 24 of the fixture 20 has a bottom geometricalconfiguration, for instance a lobe shaped geometrical configuration 27,and the protruding bottom part of the abutment 10 has a correspondinggeometrical configuration 18 as illustrated in FIGS. 15, 16 and 17, toprevent otherwise resist against rotation between these two parts whencoupled together.

The abutment 10 may have a substantially curved, conical outer surfacewith the upper edge having the wider diameter and the bottom,fixture-connecting part having a smaller diameter, as illustrated. Afeature in these particular embodiments for the three different examplesof abutments 10 illustrated in FIGS. 15, 16 and 17 may be that thebottom tapered outer surface 12 which cooperates with the annular corner26 of the fixture 20 when the two parts are coupled together as shown inFIG. 18. This provides a concave outer contour of the connection betweenthe abutment and the fixture.

In this example, the deformable element is provided by the annularcorner 26. When the abutment 10 is placed in the fixture 20 and theabutment screw 30 is tightened as previously described, the abutmentbase 12, (in this case acting as the corresponding contact surface) ispressed down onto annular corner 26, which deforms to provide a sealbetween abutment 10 and fixture 20. FIG. 19 shows a close up view of theseal formed therebetween.

The deformable element may also deform upon application of other force,such as by downward pressure on abutment 10, rather than, or inconjunction with, tightening of the abutment screw 30.

In some embodiments, the outer surface of the abutment 10 and/or thefixture 20 might be modified in order to improve the skin tissueintegration. Different types of structured or coated surfaces might beused, for instance hydroxyapatite (HA) coated surfaces. In this case itshould be understood that the coating might be applied on the fixtureand the abutment separately, or applied on a pre mounted implant device.

In a further embodiment of this aspect, the deformable element may beprovided on the abutment 10 as shown in FIG. 30 b, which corresponds tothe view of FIG. 19, and, in some embodiments, the deformable elementmay be in the form of an annular ring, as depicted in FIGS. 20 and 21.In the embodiment of FIG. 20, the deformable element is provided byabutment annular corner 19 on the abutment base 12. In this embodiment,the lip 25 of fixture 20 may be a more conventional rounded shape, whichprovides the corresponding contact surface for the deformable element,in this case, abutment annular corner 19. As in the previous example,abutment 10 is placed in the fixture 20 and when abutment screw 30 istightened, abutment 10 is pressed down onto fixture 20. In thisarrangement, deformable element (abutment annular corner 19) will bedeformed against the lip 25 to form a seal between the abutment 10 andthe fixture 20.

FIG. 22 is a close up view of the seal formed between the abutment 10and the fixture 20 of FIG. 21.

FIG. 23 shows an example of another embodiment of a medical implantsystem 100, comprising abutment 10, fixture 20 and abutment screw 30. Inthis example, the system is designed so as to provide a seal between theabutment 10 and the abutment screw 30. In this case, this seal isprovided by an arrangement similar and/or the same as that describedearlier with reference to FIGS. 5A, 5B, 5C, 6 and 7. With respect to theembodiment of FIG. 23, the deformable element is provided on theabutment screw 30 in the form of an angled flange that upon tighteningof abutment screw 30 (or application of other force), deforms againstthe corresponding contact surface (in this case abutment interior base14) to form the seal. FIG. 31 depicts an alternate embodiment whereengagement between the abutment screw 30 and the abutment 10 isdepicted, and the abutment interior base 14 of abutment 10 deforms.Specifically, flange 36 is pressed into the surface of the abutmentinterior base 14, to provide a seal. As will be understood from FIG. 31,in this alternate embodiment, the corresponding contact surface, in thiscase the abutment interior base 14, may itself deform slightly tofurther increase the seal formed therebetween. The degree of resultingdeformation of the abutment screw and/or the abutment may vary betweenembodiments. In some embodiments, all or substantially all of theoverall deformation may occur in the abutment screw 30, while in someembodiments, all or substantially all of the deformation may occur inthe abutment 10, while in some embodiments, the amount of deformationmay be more evenly distributed between these two components.

FIG. 24 shows another embodiment of a medical implant system 100comprising abutment 10, fixture 20 and abutment screw 30. In thisexample, the system is designed to provide a seal between abutment 10and fixture 20. In this case, the seal is provided by the samearrangement as described earlier with reference to FIGS. 14 to 19. Thatis, that the deformable element is provided on the fixture 20 in theform of an annular corner 26 provided on the lip 25 of fixture 20, thatupon tightening of abutment screw 30 9or application of other force),deforms against the corresponding contact surface (in this case abutmentbase 12) to form the seal. FIG. 32 depicts an alternate embodiment whereengagement between the bone fixture 20 and the abutment 10 is depicted.The depicted deformation of the abutment 10 is a result of the annularcorner 26 of lip 25 of the fixture 20 being pressed into the surface ofthe abutment 10, to provide a seal. As will be understood from FIG. 32,in this alternate embodiment, the corresponding contact surface, in thiscase the annular corner 26, may itself deform slightly to furtherincrease the seal formed therebetween. The degree of resultingdeformation of the fixture 20 and/or the abutment 10 may vary betweenembodiments. In some embodiments, all or substantially all of theoverall deformation may occur in the abutment 10, while in someembodiments, all or substantially all of the deformation may occur inthe bone fixture 20, while in some embodiments, the amount ofdeformation may be more evenly distributed between these two components.

FIG. 25 shows yet another embodiment of a medical implant system 100comprising abutment 10, fixture 20 and abutment screw 30. In thisexample, the system is designed to provide a seal between the abutment10 and the abutment screw 30 as well as between the abutment 10 andfixture 20. In this case, the first seal is provided by the samearrangement as described above with reference to FIG. 23. That is, thatthe deformable element is provided on the abutment screw 30 in the formof an angled flange that upon tightening of abutment screw 30 (orapplication of other force), deforms against the corresponding contactsurface (in this case abutment interior base 14) to form the seal. Thesecond seal is provided by the arrangement described above withreference to FIG. 24. That is, that the deformable element is providedon the fixture 20 in the form of an annular corner 26 provided on thelip 25 of fixture 20, that upon tightening of abutment screw 30 9orapplication of other force), deforms against the corresponding contactsurface (in this case abutment base 12) to form the seal. Accordingly,the arrangement of FIG. 25 is a combination of both the arrangements ofFIGS. 23 and 24.

In yet further embodiments, any combination of any two or more of theseals previously described may be used, including two different sealsprovided between the abutment 10 and the abutment screw 30 as shown inFIGS. 5 to 10 as well as FIGS. 11 to 13. By way of example, FIG. 33depicts yet another embodiment of a medical implant system 100comprising abutment 10, fixture 20 and abutment screw 30. In thisexample, the system is designed to provide a seal between the abutment10 and the abutment screw 30 as well as between the abutment 10 andfixture 20. In this case, the first seal is provided by the alternatearrangement as described above with reference to FIG. 23 and FIG. 31.That is, that the deformable element is provided on the abutment 10 (inthis case (in this case, abutment interior base 14) such that that upontightening of abutment screw 30 (or application of other force), theabutment 10 deforms against the corresponding contact surface of theabutment screw 30 to form the seal. The second seal is provided by thearrangement described above with reference to the alternate arrangementdescribed above with reference to FIG. 24 and FIG. 32. That is, that thedeformable element is again provided on the abutment 10 (in this case,abutment base 12) such that upon tightening of abutment screw 30 (orapplication of other force), the abutment 10 deforms against thecorresponding contact surface (annular corner 26 provided on the lip 25of fixture 20) to form the seal. Accordingly, the arrangement of FIG. 25is a combination of both the alternate arrangements of FIGS. 23 and 24described above.

It will be appreciated that the various deformable elements describedmay be provided by any suitable means, including by turning, during orafter the usual component production process.

The provision of the deformable element(s) in the various components ofthe medical implant system 100 provide for a unique method of implantingthe medical implant system.

The steps of one possible method of implanting the medical implantsystem 100 are shown in FIG. 26 a. At step 200, the abutment 10 islocated in the abutment receiving well of fixture interior 24 of thealready implanted fixture. At step 201, the abutment screw 30 isinserted in the through bore 16 of the abutment 10 and into the fixture20. In step 202, force is applied to the implant system until thedeformable element(s) deforms to provide the seal(s) between the variouscomponents of the medical implant system, thereby reducing the risk ofinfection in the user or patient. In one example, the force may beapplied by way of pressure on the abutment.

In another example, as shown in FIG. 26 b, the same steps 200 and 201may be used, however, in step 202′, the force may be applied by way oftightening the abutment screw 30. In one example, the abutment screw istightened using a torque of greater than about 15 Ncm, and includingabout 15 Ncm to about 20 Ncm, and about 20 Ncm to about 30 Ncm. In oneparticular example, the torque used is about 25 Ncm.

In some embodiments, the, or part of, the surfaces of one or more of thecomponents, such as the abutment screw 30 may be coated with afriction-reducing material such as diamond like carbon (DLC). In theseembodiments, the required torque or other force will be reduced.

FIGS. 27 a, 27 b and 27 c illustrate these steps 200, 201 and 202′. InFIG. 27 a, the abutment 10 is located inside fixture 20. In thisexample, fixture 20 has already been implanted and anchored in the bone50 of the patient's skull, in a previous procedure and allowed to heal.This example method therefore begins with the location of the abutment10 in fixture 20. This is done through an opening created in the tissue5 of the patient.

In FIG. 27 b, the abutment screw 30 is inserted into the abutment 10 andthe fixture 20 and in FIG. 27 c, the abutment screw 30 is tightenedusing an insertion tool 40. This tightening causes any deformableelements in the system to deform and form seals to reduce the risk ofbacteria entering into the micro leakage path and thus reducing risk ofinfection.

The seals may be provided as previously described, between the abutmentscrew 30 and the abutment 10, the abutment 10 and the fixture 20, orboth, with the locations of these discernible from the dotted linessuperimposed on FIG. 27 c.

Embodiments utilizing multiple deformable elements may use differenttypes of deformable elements/deformable elements of different geometriesas detailed herein and/or variations thereof.

In view of the above, it can be seen that in at least one aspect of theinvention, there is a medical implant system for attaching a hearingdevice to a user is provided. In one form, the medical implant systemcomprises a fixture, an abutment and an abutment screw for connectingthe abutment to the fixture. In this aspect, there is provided on one ormore of these components, a deformable element that deforms to form aseal between the one or more components of the medical implant system.

In view of the above, it can be seen that in at least one other aspectof the invention, there is an abutment for use in a medical implantsystem comprising a fixture, the abutment and an abutment screw. In oneform, the abutment comprises a through bore for receiving the abutmentscrew and a deformable element that is deformed against the abutmentscrew when the abutment screw is inserted in the through bore andtightened.

In view of the above, it can be seen that in at least one other aspectof the invention, there is an abutment screw that comprises a head, anelongate main body and a deformable element that may be deformed betweenthe abutment screw and an abutment to provide a seal upon inserting theabutment screw through the through bore of the abutment and tighteningthe abutment screw.

In view of the above, it can be seen that in at least one other aspectof the invention, there is a fixture for use in a medical implantsystem. The fixture comprises a main body, an abutment receiving welland a screw thread for anchoring the fixture into bone. In one form, adeformable element is provided as an annular corner of the abutmentreceiving well.

In view of the above, it can be seen that in at least one other aspectof the invention, there is a method of implanting a medical implantsystem into a user. The medical implant system comprises a fixture, anabutment and an abutment screw. The method involves locating theabutment in an abutment receiving well of the fixture, inserting theabutment screw in a through bore of the abutment and into the fixture,and applying a force to the implant. In one form, this force is providedby tightening the abutment screw until a deformable element deforms toprovide a seal between one or more of the components of the implantsystem.

In some embodiments, the seals formed by the embodiments detailed hereinand/or variations thereof may form a hermetic seal. In some embodiments,the seal is an air tight seal.

Throughout the specification and the claims that follow, unless thecontext requires otherwise, the words “comprise” and “include” andvariations such as “comprising” and “including” will be understood toimply the inclusion of a stated integer or group of integers, but notthe exclusion of any other integer or group of integers.

It will be understood that the invention disclosed and defined in thisspecification extends to all alternative combinations of two or more ofthe individual features mentioned or evident from the text or drawings.All of these different combinations constitute various alternativeaspects of the invention.

While various embodiments of the present technology have been describedabove, it should be understood that they have been presented by way ofexample only, and not limitation. It will be apparent to persons skilledin the relevant art that various changes in form and detail can be madetherein without departing from the spirit and scope of the technology.For instance, features described as part of one implementation can beused on another implementation to yield a still further implementation.Thus, the breadth and scope of the present technology should not belimited by any of the above-described exemplary embodiments, but shouldbe defined only in accordance with the following claims and theirequivalents. All patents and publications discussed herein are herebyincorporated in their entirety by reference thereto.

What is claimed is:
 1. An extra-oral percutaneous prosthesis,comprising: a monolithic bone fixture configured to anchor to bone of arecipient via outer threads of the bone fixture, wherein the bonefixture also includes internal threads; an external removable unit of apercutaneous bone conduction device including a vibrator, wherein theexternal removable unit transforms sound into mechanical vibrations; amonolithic abutment configured to be retainably connected to the bonefixture, wherein a distal portion of the abutment is further configuredto be in direct contact with the bone fixture and a proximal portion ofthe abutment defines a coupling portion configured to couple with andsupport the external removable unit to be connected to the bone fixture,wherein the abutment comprises an inner wall and an inner bottom; and ascrew having a head, the screw configured be extended through theabutment, so as to bolt the abutment to the bone fixture by threadingwith the internal threads of the bone fixture such that the head restson the abutment at a distance away from the bone fixture, wherein atleast one of the bone fixture or the abutment includes a deformableelement comprising at least one of a projecting element or an annularcorner configured to deform to form an anti-microbial seal between thebone fixture and the abutment establishing a seal between an interior ofthe prosthesis and an external environment, wherein the deformableelement and at least one of the bone fixture or the abutment form amonolithic structure, and is configured to deform upon threadablytightening of the screw, thereby pressing the abutment against the bonefixture to form the anti-microbial seal, and wherein the deformableelement is configured to at least one of plastically or elasticallydeform against a contact surface of the other of the abutment or bonefixture.
 2. The prosthesis of claim 1, wherein: the deformable elementis part of the bone fixture.
 3. The prosthesis of claim 2, wherein: thecontact surface is a contact surface of the abutment, and the deformableelement is configured to deform against the contact surface of theabutment, and the deformable element includes the annular corner and isconfigured such that the corner deforms against the contact surface whenthe contact surface is pressed against the corner while the contactsurface is at an oblique angle relative to the corner.
 4. The prosthesisof claim 1, wherein: the deformable element is part of the abutment. 5.The prosthesis of claim 4, wherein: the contact surface is a contactsurface of the bone fixture, and the deformable element is configured todeform against the contact surface of the bone fixture, and thedeformable element includes the annular corner and is configured suchthat the corner deforms against the contact surface when the contactsurface is pressed against the corner while the contact surface is at anoblique angle relative to the corner.
 6. The prosthesis of claim 1,wherein the abutment comprises an interior base surface including aplurality of openings therein spaced apart from one another.
 7. Theprosthesis claim 1, wherein the deformable element is configured toplastically deform to form the anti-microbial seal.
 8. The prosthesis ofclaim 1, wherein: the deformable element deforms to compensate forsurface imperfections of the contact surface to form the anti-microbialseal.
 9. The prosthesis of claim 1, wherein the deformable element ofthe bone fixture or the abutment is configured to deform against thecontact surface of the other of the bone fixture or abutment, therebyreducing at least one of gaps or holes between the deformable elementand the contact surface otherwise passable therethrough by microbes toform the anti-microbial seal.
 10. The prosthesis of claim 1, wherein theanti-microbial seal is an air tight seal.
 11. The prosthesis of claim 1,wherein: the bone fixture includes a female portion; the abutmentincludes a male portion; and at least a portion of the male portion ofthe abutment is located in at least a portion of the female portion ofthe bone fixture.
 12. The prosthesis of claim 1, wherein: the bonefixture includes a female portion; the abutment includes a male portion;and all portions of the bone fixture are located outside of theabutment.
 13. The prosthesis of claim 1, wherein the deformable elementis configured to elastically deform to form the anti-microbial seal.